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arXiv · 0901.2519

Asymmetric noise probed with a Josephson junction

Q. Le Masne·H. Pothier·Norman O. Birge·C. Urbina·D. Esteve
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Abstract

Fluctuations of the current through a tunnel junction are measured using a Josephson junction. The current noise adds to the bias current of the Josephson junction and affects its switching out of the supercurrent branch. The experiment is carried out in a regime where switching is determined by thermal activation. The variance of the noise results in an elevated effective temperature, whereas the third cumulant, related to its asymmetric character, leads to a difference in the switching rates observed for opposite signs of the current through the tunnel junction. Measurements are compared quantitatively with recent theoretical predictions.

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Q. Le Masne, H. Pothier, Norman O. Birge, C. Urbina, D. Esteve. 2009-01-16. Asymmetric noise probed with a Josephson junction. https://doi.org/10.1103/physrevlett.102.067002

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